1. Field of the Invention
The present invention relates to braking systems for trailers and more particularly to systems for controlling sway and for applying the trailer brakes.
2. Description of the Prior Art
Trailers, such as mobile homes, travel trailers, campers and the like, are conventionally equipped with electrically actuable brakes which may be operated by the driver in the towing automobile. During travel in excess of predetermined speeds the hazardous condition of trailer sway may occur and this is inhibited by momentary application of the trailer brakes. Such momentary application results from briefly energizing the brake-actuating coils by means of manually or automatically operable devices. Typical of such devices are those disclosed in U.S. Pat. Nos. 3,840,276; 3,861,489; 3,758,165; 3,288,240; 3,819,234; 3,908,782; 3,895,683; 3,243,192 and 4,023,864.
A "sway" condition is typified by the trailer rapidly swinging from side to side as opposed to moving to one side or swerving as in rounding a curve. As is well known, such sway is inherently hazardous and can be the cause of an accident.
Many prior art systems have been employed to minimize or eliminate sway. Some of the mechanical and electrical apparatuses heretofore used suffer the disadvantage of not only functioning to correct the sway but also to apply braking resistance during rounding a turn or curve.
It is desirable at times to apply the trailer brakes without applying the brakes of the towing vehicle. Many of the prior art sway control systems have no such capability. Others utilize electro-mechanical devices which lack reliability and facile control of brake application.